Improvement in steam-engine-piston valves



v of the cylinder and steam-chest, showing the operation through theport j'-, into the cylinder at its left-hand or G *www 'M atwtlttiteRICHARD GORNALL, 0F BALTIMORE, MARYLAND.

Letters Patent No. 82,936,

dated october 13, 186s.

f The Schedule referredto ,in these Letten; Patent and making part ofthe same.

To all whom it may concern: v

Beit known that I, RICHARD GORNALL, of the city and county of Baltimore,and'State of Maryland, have invented a new and improved Water andSteam-Valve and Cylinder; and I do hereby declare the following to'be afull, clear, and exact description of the same, suiiicient to enablethose skilled in the art towhich my invention appert-ains to make use ofit,rreference being had to the accompanying drawings, forming part ofthis specification, and in which- Figure l is a longitudinal sectionthrough the centre of the valves at one part of the stroke, and

Figure 2 is a similar section, showing the position of the valvs atanother part of the stroke'.

In this invention, the cylinder-valvesY are worked by the direct actionof the live steam, Without the intervention of tappets, eccentrics,cams, or any other device outside of the steam-chest and cylinder.

In the drawings, A is the cylinder; B, the steamchest; C, the mainslide-valve; Dra slide-valve extending longitudinally through the mainvalve; F is the piston; G is the piston-rod; I is the induction-pipe;and J the exhaust. f v

At the beginning of the stroke, the valves being in the position shownin fig. l, the steam enters from the cylinder through the passage a clto an aperture, a2, with which the passage a is then in communication,and fills a chamber, d, in the end 0f the valve D, where it expandsagainst the end of the steam-chest and forces the valve D back from theend of the steam-chest until its terminal flanges, e c, rest againstthe4 end of the main valve, as seen in iig. 2, the position of the mainvalve being yet unchanged. Y

This movement of the valve D cuts o the communication from the passagea) to the aperture a2, and opens a free communication from the cylinderto the chamber d, through the passages a a* and c.

The steam entering the chamber d, then, with great force, acts againstthe end of the steam-chest, as before, and against the end of the valveD and the main valve C, and drives them both together toward the otherend of the steam-chest.

jj is a port or passage running in behind the passage a, which sometimesconnects the right-hand end of the cylinder with the induction-pipe, andsometimes with the exhaust, according to the position of the main valve;and j j is a corresponding port or passage connecting the left-hand endof the cylinder with the eX- haust and induction in the same Way.

When the main valve is inthe position shown in iig; l, the steam om theinduction-pipe I passes into the port t', then around behind the mainvalve, and

upper end, driving the piston down, or to the right, and bringing it tothe position shown ing. 1.

f While the piston is passing from the upper to the 'the main valve C,in the manner above described.

While the piston is at the upper end of the cylinder, and until it haspassed to the lower or right-hand end,

rthe steam exhausts from the lower lVend, through the passage jj and therecess J in the side of the main valve, to the pipe J, which leads tothe condenser or to the open air. l Y 'A v The action of the steam inVthis manner will, as

' before remarked, change the position of the valves -with greatrapidity from the lower to the .upper end of the steam-chest, where theywill assume the same `relative position that they occupied before theycom-` menced to move from the lower end, as shown in fig. 1. Thisreversing of the position ofthe valves reverses the whole action of thesteam anilthe motion ofthe piston.

The recessJ is brought over the port j', and the passage t. isdisconnected from the induction, cutting ofi` the live steam" from 'theupper end of the cylinder, and opening the wayfrom that end to theexhaust,

while the recess J disconnected from the port j j, l

and the live steam Afrom the induction is let linto the latter through apassage, i, similar in formation and operation to that designated as i',and which has already been described. The steam now entering below or tothe right of the piston, forces -the latter back to the upper end of thecy1inder,.where the same action will take place to drive the valves backthat took place in the first instance to drive them from the positionshown iniig. 1, and this alternating and reciprocating action of thevalves and the piston will continue as long as there is steam enough towork the parts.

There -is a point inthe stroke where for a moment the induction steamwould be entirely shut off were not some provisionmade to prevent it,and the' action of the mechanism might be interfered with to some extentthereby. That point is at the moment when l the valves are midwaybetween the ends of the steam chest, so that the solid metal of the mainvalve at m, between the passages i and '11', covers and closes theinduction-port. This diticulty is, however, entirely remedied by theemployment of auxiliaryports, 'n n',

Aconnecting with two passages, c fr, leading from the induction-pipes ateach side of the port, and passing around behind the main valve,entering the chambers d d at o o.

When the main valve is at either end of' its stroke, or in such aposition that the live steam can pass to the cylinder, the passages frlr are disconnected from the ports n n; but whenever the main valvegetsinto such a position that the induction steam is cut oli by the partm, then the passages lr r and ports n a' will be incommunication witheach other, and the live steam will freely enter the passages 'r r andpass toward the chambers d d', one of which it will enter,

. the opposite or exhaust end of the steam-chest. This is eected `bymeans of the interior Sliding valve D. When the flange e of this valvelies against the end l of the main valve, a communication is openbetween the chamber d or d' in that end of the valve D and the passage ror fr leading toward it, and when the ange does not lie against the endof the main valve, such communication is closed.

The iange being caused to seat upon' the end of the main valve only bythe action ofthe live steam in the end vof the steam-chest from whichthe valves are receding, it follows that, at the, proper moment, whenthe valves are passing from iight to lett, the induction steam willbelet into the chamber d, and when they are passing in the oppositedirection, it will be let into the chamber d', acting, into whicheverchamber it is let, to push the main valve past that portion of itsstroke where the induction steam was cut off by the part m, as abovedescribed.

The position of the valves, with the main induction g cut oi and theauxiliary valve-inductions open, is shown clearly in fig. 2.

While the steam is passing to the chamber d or d', to assist in movingthe valve past the dead-point, as above described, it will not do tohave that chamber communicate with the main exhaust or the interior ofthe cylinder. Accordingly, at this pointof the stroke `a small plate, u,in an enlargement of the passagea', at the edge of the main valve, shutsover the end of the passage a, and severs the communication for the timebetween the two passages. By the time when the main induction is openagain, the plate 'u has passed over the end of the passage a, and thecommunication from the cylinder to the valvefchamber is restored.

s s' is the valve-exhaust, communicating with the main exhaust through apassage, t t', which runs round behind the valve D.

P P are springs, and P P' tempering-screws to regulate them, which serveas cushions to the valves.

W is a rod, having an eye, w, on its outer extremity,

in and also serves as a means by which the valve may be worked loose incase it becomes stii with rust or t obstructed with sediment.

In order to reverse the engine with this rod, it will only be necessaryto shut olf the induction steam, and by means of the rod 4force the mainvalve back to the end of the steam-chest opposite to that at which it isstanding at the time. t

The operation of this engine is exceedingly regular, uniform, rapid, andpowerful. It has been thoroughly tried, and found to'workadmrablyi t tBy dispensing with 1verods operating outside of the steam-chest, thecylinder may be` brought within four-'or five inchesvof a pump-barrel orother instrument, which the engine is intended to work, and theexpensive cylinder packing hitherto required when the t engine isapplied to such purposes, may be entirely dispensed with. In place ofsuch packing, a simple split bushing may be used, packed in any suitablemanner, and conneddn position by any suitable means. Besides the savingof this expense,\the `space saved by the use of my form of engine `willoften be of` no inconsiderable importance.-` t V t x j t It is evidentthat the principle of construction embraced in my invention may beemployed in connection with engines working with any kind ofmotive-power that operates a piston in a cylinder by means of anarrangement of valves. l

Having thus described my invention, t.

What I claim as new, and desire to secure by Lette Patent, is-

' 1. The combinationof the main valve O with the interior sliding valve`D, havingthe flanges e e, substantially as and for the purposesspecified.

2. In combination with the valve C and the interior sliding valve D, Iclaim the auxiliary steam-ports n n', substantially as and for thepurpose specified.

. RICHARD GORNALL.

Witnesses: l

Enwnnn tTomi Bamm, WILLIAM ELIAS Swans.

